Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to i...Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to its therapeutic properties,but its exact role and molecular mechanisms in treatment of reproductive dysfunction remain unclear.Methods:During this study,36 rats were randomly divided into six groups(n=6):control,CYP-induced(60 mg/kg),standard(leuprolide 3 mg/kg)and three treatment groups receiving aqueous,ethanolic,and oil extracts(50 mg/kg or 20 mL/kg)for post-toxicity induction.Results:The finding represented that exposure of CYP significantly increased oxidative stress,disrupted testicular architecture,and markedly reduced testosterone levels(P<0.05).Importantly,Crocus sativus L.treatment alleviated these changes by increasing the expression of Nrf2(nuclear factor erythroid 2-related factor 2),restoring the activity of antioxidant enzymes,and enhancing testicular histomorphology.Surprisingly,molecular docking established a high binding affinity of Crocus sativus L.phytoconstituents such as gallic acid,cinnamic acid and quercetin to the Nrf2-Keap1 complex.It is worth noting that,Crocus sativus L.exhibited a high level of protection against reproductive toxicity caused by CYP in male rats,which was mediated by the activation of Nrf2 pathway,reduction of oxidative damage,and favorable ADMET characteristics.Conclusion:Notably,this research provides a more valid,safe,and effective method of developing new drugs for reproductive disorders,however,further investigation is needed to support the research findings and implement it in clinical practice.展开更多
The electrochemical reduction of carbon dioxide(CO_(2))into value-added chemicals and fuels has been extensively studied as a promising strategy for mitigating environmental issues and achieving sustainable energy con...The electrochemical reduction of carbon dioxide(CO_(2))into value-added chemicals and fuels has been extensively studied as a promising strategy for mitigating environmental issues and achieving sustainable energy conversion.Substantial efforts have been made to improve the understanding of CO_(2)reduction reaction(CO_(2)RR)mechanisms by computational and spectroscopic studies.An in-depth understanding of CO_(2)RR mechanism can provide the guidance and criteria for designing high-efficiency catalysts,and hence,steering CO_(2)RR to desired products.This review systematically discusses the formation mechanisms and reaction pathways of various CO_(2)RR products,including C_(1)products(CO,HCOOH,and CH_(4)),C_(2)products(C_(2)H_(4),C_(2)H_(5)OH,and CH_(3)COOH),and C_(3+)products(C_(3)H_(6),C_(3)H_(7)OH,and others).The reaction pathways are elucidated by analyzing the adsorption behavior,energy barriers,and intermediate coupling steps involved in the generation of each product.Particular emphasis is placed on the key intermediates,such as^(*)OCHO,^(*)COOH,^(*)CO,^(*)OCCOH,and^(*)CCO,which play crucial roles in determining the product selectivity.The effects of catalyst composition,morphology,and electronic structure on the adsorption and activation of these intermediates are also discussed.Moreover,advanced characterization techniques,including in-situ spectroscopy and isotopic labeling experiments,are highlighted for their contributions to unraveling the reaction mechanisms.The review aims to provide critical insights to reveal the activity-determining para meters and underlying CO_(2)RR mechanisms,which will guide the rational design of next-generation electrocatalysts for selective CO^(2)RR towards high-value products.展开更多
Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration vi...Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration via paracrine signaling;however,their clinical applications are limited by potential risks such as tumorigenesis and xenogeneic immune rejection,which are similar to the risks associated with other stem cell transplantations.The present study therefore focuses on small extracellular vesicles derived from hair follicle neural crest stem cells,which preserve the bioactive properties of the parent cells while avoiding the transplantation-associated risks.In vitro,small extracellular vesicles derived from hair follicle neural crest stem cells significantly enhanced the proliferation,migration,tube formation,and barrier function of perineurial cells,and subsequently upregulated the expression of tight junction proteins.Furthermore,in a rat model of sciatic nerve defects bridged with silicon tubes,treatment with small extracellular vesicles derived from hair follicle neural crest stem cells resulted in higher tight junction protein expression in perineurial cells,thus facilitating neural tissue regeneration.At 10 weeks post-surgery,rats treated with small extracellular vesicles derived from hair follicle neural crest stem cells exhibited improved nerve function recovery and reduced muscle atrophy.Transcriptomic and micro RNA analyses revealed that small extracellular vesicles derived from hair follicle neural crest stem cells deliver mi R-21-5p,which inhibits mothers against decapentaplegic homolog 7 expression,thereby activating the transforming growth factor-β/mothers against decapentaplegic homolog signaling pathway and upregulating hyaluronan synthase 2 expression,and further enhancing tight junction protein expression.Together,our findings indicate that small extracellular vesicles derived from hair follicle neural crest stem cells promote the proliferation,migration,and tight junction protein formation of perineurial cells.These results provide new insights into peripheral nerve regeneration from the perspective of perineurial cells,and present a novel approach for the clinical treatment of peripheral nerve defects.展开更多
Ulcerative colitis(UC)is an idiopathic,relapsing,and etiologically complicated chronic inflammatory bowel disease.Despite substantial progress in the management of UC,the outcomes of mucosal barrier repair are unsatis...Ulcerative colitis(UC)is an idiopathic,relapsing,and etiologically complicated chronic inflammatory bowel disease.Despite substantial progress in the management of UC,the outcomes of mucosal barrier repair are unsatisfactory.In this study,phillygenin(PHI)treatment alleviated the symptoms of chronic colitis in mice,including body weight loss,severe disease activity index scores,colon shortening,splenomegaly,oxidative stress,and inflammatory response.In particular,PHI treatment ameliorated the tight junction proteins(TJs)reduction,fibrosis,apoptosis,and intestinal stem cell activity,indicating that PHI exerted beneficial effects on the intestinal mucosal barrier in mice with chronic colitis.In the NCM460 cells damage model,dextran sulfate sodium triggered the sequential induction of TJs reduction,fibrosis,and apoptosis.Takeda G protein-coupled receptor-5(TGR5)dysfunction mediated NCM460 cell injury.Moreover,PHI treatment enhanced TJs and suppressed fibrosis and apoptosis to maintain NCM460 cell function,depending on TGR5 activation.PHI promoted TGR5 activation and elevated intracellular cyclic adenosine monophosphate levels in HEK 293T cells transfected with TGR5 expression plasmids.Cellular thermal shift assay and molecular docking studies confirmed that PHI directly binds to TGR5,indicating that PHI is an agonist of TGR5.The process of PERK-eIF2α pathway-mediated endoplasmic reticulum Ca^(2+) release was involved in NCM460 cell injury as well,which was associated with TGR5 dysfunction.When NCM460 cells were pretreated with PHI,the PERK-eIF2α pathway and elevated Ca^(2+) levels were blocked.In conclusion,our study demonstrated a novel mechanism that PHI inhibited the PERK-eIF2α-Ca^(2+) pathway through TGR5 activation to against DSS-induced TJs reduction,fibrosis,and apoptosis.展开更多
The need to secure environmentally sustainable sources of clean fuel has led to intensive research into the catalytic conversion of CO_(2)into valuable C_(2)+compounds.However,the intrinsically sluggish reduction kine...The need to secure environmentally sustainable sources of clean fuel has led to intensive research into the catalytic conversion of CO_(2)into valuable C_(2)+compounds.However,the intrinsically sluggish reduction kinetics and competing reaction pathways present challenges in achieving high product selectivity and efficiency.Herein,we focus on the transformation of CO_(2)into C_(2)+products,particularly emphasizing advances in non-copper-based catalytic systems,which have emerged as promising alternatives that present unique electronic structures and adsorption properties.Unlike conventional copper catalysts,these systems offer distinct advantages in selectivity and stability,particularly through the modulation of surface defect engineering.We systematically analyze the main reaction pathways leading to C_(2)+products,including ethylene formation and higher hydrocarbon(C_(2)-4)alcohols and oxygenates,while critically assessing the mechanistic insights that differentiate non-copper catalysts from their Cu-based counterparts.By summarizing recent developments,the key challenges,and optimization strategies,we provide a comprehensive overview of how non-copper catalysts can enable efficient and scalable CO_(2)reduction reactions,with an aim of assisting researchers in their design of novel catalysts that may reach industrial applications.展开更多
Photocatalytic oxygen reduction for hydrogen peroxide(H_(2)O_(2))synthesis presents a green and costeffective production method.However,achieving highly selective H_(2)O_(2)synthesis remains challenging,necessitating ...Photocatalytic oxygen reduction for hydrogen peroxide(H_(2)O_(2))synthesis presents a green and costeffective production method.However,achieving highly selective H_(2)O_(2)synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative by-products.Herein,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H_(2)O_(2)and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride(CNRb).The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h^(-1)for H_(2)O_(2)generation and photooxidation rate of 3.75 mM h^(-1)for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion(SCC)efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical formation.This is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product formation.This study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H_(2)O_(2)coupled with biomass valorization.展开更多
Objective:To examine the effect of shikonin against streptozotocin(STZ)-induced diabetic retinopathy in rats and elucidate the underlying mechanisms.Methods:Intraperitoneal administration of STZ(65 mg/kg)was used for ...Objective:To examine the effect of shikonin against streptozotocin(STZ)-induced diabetic retinopathy in rats and elucidate the underlying mechanisms.Methods:Intraperitoneal administration of STZ(65 mg/kg)was used for the induction of diabetic retinopathy in rats.Rats received oral administration of shikonin(10,20,and 30 mg/kg).The blood glucose level,insulin,body weight,and organ weight were estimated.Advanced glycation end products(AGEs)levels in serum and lens as well as protein carbonyl content of the lens were determined.The parameters related to oxidative stress and inflammation,and the levels of nuclear factor erythroid 2-related factor 2(Nrf2),heme oxygenase-1(HO-1),intercellular adhesion molecule-1(ICAM-1),and vascular cell adhesion molecule 1(VCAM-1)were also measured.In addition,quantitative RT-PCR was performed to determine the mRNA expressions.Results:Shikonin treatment decreased glucose level and boosted insulin level,along with an increase in body weight and improved organ weight.It also lowered O2•−,ONOO−,serum and lens AGEs,and protein carbonyl content.Furthermore,shikonin treatment significantly alleviated oxidative stress and inflammation,as evidenced by reduced malonaldehyde,nitric oxide,tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),IL-6,cyclooxygenase-2,prostaglandin E2,protein carbonyl content,and nuclear factor kappa-B,and increased superoxide dismutase,glutathione,catalase,and glutathione peroxidase.Markedly decreased levels of ICAM-1 and VCAM-1,as well as heightened levels of Nrf2 and HO-1,were noticed after treatment with shikonin.Furthermore,the mRNA expressions of TNF-α,IL-1β,IL-6,ICAM-1,VCAM-1,RAGE,collagenⅣ,and fibronectin were significantly downregulated.Conclusions:Shikonin exhibits protective effects against STZ-induced diabetic retinopathy in rats via modulating the Nrf2/HO-1 and NF-κB signaling pathways.展开更多
Electrochemical carbon dioxide reduction reaction(CO_(2)RR)converts CO_(2) into valuable chemicals by consuming renewable electricity at mild conditions,making it a promising approach to achieving carbon neutrality.Ho...Electrochemical carbon dioxide reduction reaction(CO_(2)RR)converts CO_(2) into valuable chemicals by consuming renewable electricity at mild conditions,making it a promising approach to achieving carbon neutrality.However,the reaction of CO_(2) with hydroxide ions to form carbonates leads to low carbon utilization and energy efficiency in near-neutral or alkaline CO_(2)RR.The high concentration of protons in acidic media can effectively mitigate carbonate formation and deposition,thereby significantly minimizing carbon loss and energy consumption.Unfortunately,hydrogen evolution reaction(HER)is more kinetically favorable than CO_(2)RR in acidic media.Herein,we comprehensively overview recent progress in acidic CO_(2)RR and propose two strategies derived from the competing reaction pathways of HER and CO_(2)RR:one focuses on regulating the H+mass transport,while the other aims to modulate the intrinsic kinetic activity of CO_(2)RR.The two strategies are designed to compete for the limited active sites on the catalyst surface,inhibit side reactions,and enhance the activity and selectivity of CO_(2)RR.The representative approaches include modulating the interface electric field,constructing a local alkaline environment,and regulating competing adsorption sites.Finally,we also review the technical challenges and future perspectives of acidic CO_(2)RR coupled with membrane electrode assemblies(MEAs).展开更多
Background:Dry eye disease(DED)predominantly results from elevated tear film os-molarity,which can not only cause ocular inconvenience but may lead to visual impair-ments,severely compromising patient well-being and e...Background:Dry eye disease(DED)predominantly results from elevated tear film os-molarity,which can not only cause ocular inconvenience but may lead to visual impair-ments,severely compromising patient well-being and exerting substantial economic burdens as well.Astaxanthin(AST),a member of the xanthophylls and recognized for its robust abilities to combat inflammation and oxidation,is a common dietary sup-plement.Nonetheless,the precise molecular pathways through which AST influences DED are still poorly understood.Methods:Therapeutic targets for AST were identified using data from the GeneCards,PharmMapper,and Swiss Target Prediction databases,and STITCH datasets.Similarly,targets for dry eye disease(DED)were delineated leveraging resources such as the Therapeutic Target Database(TTD),DisGeNET,GeneCards,and OMIM databases,and DrugBank datasets.Interactions among shared targets were charted and dis-played using CytoScape 3.9.0.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were conducted to elucidate the functions of pivotal tar-gets within the protein-protein interaction network.Molecular interactions between AST and key targets were confirmed through molecular docking using AutoDock and PyMOL.Molecular dynamics simulations were performed using GROMACS 2022.3.Viability of human corneal epithelial cells(hCEC)was assessed across varying concen-trations of AST.A mouse model of experimental DED was developed using 0.1%ben-zalkonium chloride(BAC),and the animals were administered 100 mg/kg/day of AST orally for 7 days.The efficacy of the treatments was assessed through a series of di-agnostic tests to evaluate the condition of the ocular surface after the interventions.The levels of inflammation and oxidative stress were quantitatively assessed using methods such as reverse transcription-polymerase chain reaction(RT-PCR),Western blot,and immunofluorescence staining.Results:Network pharmacology suggests that AST may alleviate DED by influenc-ing oxidation-reduction signaling pathways and reducing oxidative stress provoked by BAC.In vivo experiments demonstrated an improved overall condition in AST-administered mice in contrast to the control group.Immunofluorescence staining analyses indicated a decrease in Keap1 protein in the corneal tissues of AST-treated mice and a significant increase in Nrf2 and HO-1 protein.In vitro studies demon-strated that AST significantly enhanced cell viability and suppressed reactive oxy-gen species expression under hyperosmotic(HS)conditions,thereby protecting the human corneal epithelium.Conclusion:AST is capable of shielding mice from BAC-induced DED,decelerating the progression of DED,and mitigating oxidative stress damage under HS conditions in hCEC cells.The protective impact of AST on DED may operate through stimulating the Keap1-Nrf2/HO-1 signaling pathway.Our research findings indicate that AST may be a promising treatment for DED,offering new insights into DED treatment.展开更多
A meticulous design of the local environment at the interface between active species and the support,aimed at optimizing the adsorption of H_(2)O molecules and BH_(4)^(-)anion,offers an ideal strategy for enhancing hy...A meticulous design of the local environment at the interface between active species and the support,aimed at optimizing the adsorption of H_(2)O molecules and BH_(4)^(-)anion,offers an ideal strategy for enhancing hydrogen generation via Na BH4hydrolysis through dual activation pathways.Theoretical predictions based on d-band center analysis and electron transfer calculations suggest that introducing-OH functional groups induce charge redistribution,enhancing charge concentration on alk-Ti_(3)C_(2)and facilitating the adsorption and activation of dual active species,H2O molecules and BH4-anion.Inspired by these predictions,the optimized alk-Ti_(3)C_(2)/Ru Oxcatalyst demonstrates the highest catalytic activity,achieving a hydrogen generation rate(HGR)of 9468 m L min^(-1)gcat.^(-1).Both experimental data and theoretical analyses confirm that the-OH functional groups promote charge enrichment on alk-Ti_(3)C_(2),optimizing the adsorption of H_(2)O molecules and BH_(4)^(-)anion,and reducing the dissociation energy barrier of the*OH–H-TS intermediate.This dual activation pathways mechanism lowers the activation energy for Na BH4hydrolysis,significantly enhancing the HGR performance.These findings,guided by theoretical insights,establish alk-Ti_(3)C_(2)/Ru Oxas an efficient catalyst for Na BH4hydrolysis and provide a strong foundation for future hydrogen generation catalyst designs.展开更多
WT5”BZ] To study the molecular mechanism of the stimulatory effect of low dose radiation(LDR) on T cell activation. [WT5”BX]Methods.[WT5”BZ] Thymocytes from Kunming mice exposed to whole body irradiation(WBI) with ...WT5”BZ] To study the molecular mechanism of the stimulatory effect of low dose radiation(LDR) on T cell activation. [WT5”BX]Methods.[WT5”BZ] Thymocytes from Kunming mice exposed to whole body irradiation(WBI) with different doses of X rays were analyzed for the changes in signal molecules of the phospholipase C phosphatidylinositol biphosphate(PLC IP2) and G protein adenylate cyclase(AC) pathways. [WT5”BX]Results.[WT5”BZ]It was found that[Ca 2+ ] i increased in response to doses within 0 2 Gy which was most marked after 0 075 Gy and the increase was accentuated in the presence of Con A. The changes in CD3 and calcineurin(CN) expression of the thymocytes followed the same pattern as the alterations in [Ca 2+ ] i after LDR. The expression of α,β1 and β2 isoforms of protein kinase C(PKC) was all up regulated after 0 075 Gy with the increase in PKC β1 expression being most marked. The cAMP/cGMP ratio and PKA activity of the thymocytes was lowered after low dose radiation and increased after doses above 0 5 Gy in a dose dependent manner, thus giving rise to J shaped dose response curves. The Ca antagonist TMB 8 and cAMP stimulant cholera toxin suppressed the augmented thymocyte proliferation induced by LDR. [WT5”BX]Conclusion.[WT5”BZ]Data presented in the present paper suggest that activation of the PLC PIP2 signal pathway and suppression of the AC cAMP signal pathway are involved in the stimulation of the thymocytes following WBI with low dose X rays.展开更多
文摘Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to its therapeutic properties,but its exact role and molecular mechanisms in treatment of reproductive dysfunction remain unclear.Methods:During this study,36 rats were randomly divided into six groups(n=6):control,CYP-induced(60 mg/kg),standard(leuprolide 3 mg/kg)and three treatment groups receiving aqueous,ethanolic,and oil extracts(50 mg/kg or 20 mL/kg)for post-toxicity induction.Results:The finding represented that exposure of CYP significantly increased oxidative stress,disrupted testicular architecture,and markedly reduced testosterone levels(P<0.05).Importantly,Crocus sativus L.treatment alleviated these changes by increasing the expression of Nrf2(nuclear factor erythroid 2-related factor 2),restoring the activity of antioxidant enzymes,and enhancing testicular histomorphology.Surprisingly,molecular docking established a high binding affinity of Crocus sativus L.phytoconstituents such as gallic acid,cinnamic acid and quercetin to the Nrf2-Keap1 complex.It is worth noting that,Crocus sativus L.exhibited a high level of protection against reproductive toxicity caused by CYP in male rats,which was mediated by the activation of Nrf2 pathway,reduction of oxidative damage,and favorable ADMET characteristics.Conclusion:Notably,this research provides a more valid,safe,and effective method of developing new drugs for reproductive disorders,however,further investigation is needed to support the research findings and implement it in clinical practice.
基金financially supported by the National Natural Science Foundation of China(Grants 22225901,21975237 and 51702312)the Fundamental Research Funds for the Central Universities(Grant WK2340000101)+5 种基金the USTC Research Funds of the Double First-Class Initiative(Grant YD2340002007 and YD9990002017)the Open Funds of the State Key Laboratory of Rare Earth Resource Utilization(Grant RERU2022007)the China Postdoctoral Science Foundation(Grants 2023M733371,2024M750006 and 2023T160617)Postdoctoral Fellowship Program(Grade C)of China Postdoctoral Science Foundation(GZC20230008)the Natural Science Foundation Youth Project of Anhui Province(2408085QB065)the Postdoctoral Research Funding Project of Anhui Province(2023B727)。
文摘The electrochemical reduction of carbon dioxide(CO_(2))into value-added chemicals and fuels has been extensively studied as a promising strategy for mitigating environmental issues and achieving sustainable energy conversion.Substantial efforts have been made to improve the understanding of CO_(2)reduction reaction(CO_(2)RR)mechanisms by computational and spectroscopic studies.An in-depth understanding of CO_(2)RR mechanism can provide the guidance and criteria for designing high-efficiency catalysts,and hence,steering CO_(2)RR to desired products.This review systematically discusses the formation mechanisms and reaction pathways of various CO_(2)RR products,including C_(1)products(CO,HCOOH,and CH_(4)),C_(2)products(C_(2)H_(4),C_(2)H_(5)OH,and CH_(3)COOH),and C_(3+)products(C_(3)H_(6),C_(3)H_(7)OH,and others).The reaction pathways are elucidated by analyzing the adsorption behavior,energy barriers,and intermediate coupling steps involved in the generation of each product.Particular emphasis is placed on the key intermediates,such as^(*)OCHO,^(*)COOH,^(*)CO,^(*)OCCOH,and^(*)CCO,which play crucial roles in determining the product selectivity.The effects of catalyst composition,morphology,and electronic structure on the adsorption and activation of these intermediates are also discussed.Moreover,advanced characterization techniques,including in-situ spectroscopy and isotopic labeling experiments,are highlighted for their contributions to unraveling the reaction mechanisms.The review aims to provide critical insights to reveal the activity-determining para meters and underlying CO_(2)RR mechanisms,which will guide the rational design of next-generation electrocatalysts for selective CO^(2)RR towards high-value products.
基金supported by the National Natural Science Foundation of China,No.81571211(to FL)the Natural Science Foundation of Shanghai,No.22ZR1476800(to CH)。
文摘Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration via paracrine signaling;however,their clinical applications are limited by potential risks such as tumorigenesis and xenogeneic immune rejection,which are similar to the risks associated with other stem cell transplantations.The present study therefore focuses on small extracellular vesicles derived from hair follicle neural crest stem cells,which preserve the bioactive properties of the parent cells while avoiding the transplantation-associated risks.In vitro,small extracellular vesicles derived from hair follicle neural crest stem cells significantly enhanced the proliferation,migration,tube formation,and barrier function of perineurial cells,and subsequently upregulated the expression of tight junction proteins.Furthermore,in a rat model of sciatic nerve defects bridged with silicon tubes,treatment with small extracellular vesicles derived from hair follicle neural crest stem cells resulted in higher tight junction protein expression in perineurial cells,thus facilitating neural tissue regeneration.At 10 weeks post-surgery,rats treated with small extracellular vesicles derived from hair follicle neural crest stem cells exhibited improved nerve function recovery and reduced muscle atrophy.Transcriptomic and micro RNA analyses revealed that small extracellular vesicles derived from hair follicle neural crest stem cells deliver mi R-21-5p,which inhibits mothers against decapentaplegic homolog 7 expression,thereby activating the transforming growth factor-β/mothers against decapentaplegic homolog signaling pathway and upregulating hyaluronan synthase 2 expression,and further enhancing tight junction protein expression.Together,our findings indicate that small extracellular vesicles derived from hair follicle neural crest stem cells promote the proliferation,migration,and tight junction protein formation of perineurial cells.These results provide new insights into peripheral nerve regeneration from the perspective of perineurial cells,and present a novel approach for the clinical treatment of peripheral nerve defects.
基金supported by the National Natural Science Fund of China(Grant Nos.:31800293 and 32370422)Project of Standard for TCM(Grant No.:ZYBZH-Y-JIN-34).
文摘Ulcerative colitis(UC)is an idiopathic,relapsing,and etiologically complicated chronic inflammatory bowel disease.Despite substantial progress in the management of UC,the outcomes of mucosal barrier repair are unsatisfactory.In this study,phillygenin(PHI)treatment alleviated the symptoms of chronic colitis in mice,including body weight loss,severe disease activity index scores,colon shortening,splenomegaly,oxidative stress,and inflammatory response.In particular,PHI treatment ameliorated the tight junction proteins(TJs)reduction,fibrosis,apoptosis,and intestinal stem cell activity,indicating that PHI exerted beneficial effects on the intestinal mucosal barrier in mice with chronic colitis.In the NCM460 cells damage model,dextran sulfate sodium triggered the sequential induction of TJs reduction,fibrosis,and apoptosis.Takeda G protein-coupled receptor-5(TGR5)dysfunction mediated NCM460 cell injury.Moreover,PHI treatment enhanced TJs and suppressed fibrosis and apoptosis to maintain NCM460 cell function,depending on TGR5 activation.PHI promoted TGR5 activation and elevated intracellular cyclic adenosine monophosphate levels in HEK 293T cells transfected with TGR5 expression plasmids.Cellular thermal shift assay and molecular docking studies confirmed that PHI directly binds to TGR5,indicating that PHI is an agonist of TGR5.The process of PERK-eIF2α pathway-mediated endoplasmic reticulum Ca^(2+) release was involved in NCM460 cell injury as well,which was associated with TGR5 dysfunction.When NCM460 cells were pretreated with PHI,the PERK-eIF2α pathway and elevated Ca^(2+) levels were blocked.In conclusion,our study demonstrated a novel mechanism that PHI inhibited the PERK-eIF2α-Ca^(2+) pathway through TGR5 activation to against DSS-induced TJs reduction,fibrosis,and apoptosis.
基金supported by the Joint Funds of the National Natural Science Foundation of China(U24B20201)National Natural Science Foundation of China(22372007 and 21972010).
文摘The need to secure environmentally sustainable sources of clean fuel has led to intensive research into the catalytic conversion of CO_(2)into valuable C_(2)+compounds.However,the intrinsically sluggish reduction kinetics and competing reaction pathways present challenges in achieving high product selectivity and efficiency.Herein,we focus on the transformation of CO_(2)into C_(2)+products,particularly emphasizing advances in non-copper-based catalytic systems,which have emerged as promising alternatives that present unique electronic structures and adsorption properties.Unlike conventional copper catalysts,these systems offer distinct advantages in selectivity and stability,particularly through the modulation of surface defect engineering.We systematically analyze the main reaction pathways leading to C_(2)+products,including ethylene formation and higher hydrocarbon(C_(2)-4)alcohols and oxygenates,while critically assessing the mechanistic insights that differentiate non-copper catalysts from their Cu-based counterparts.By summarizing recent developments,the key challenges,and optimization strategies,we provide a comprehensive overview of how non-copper catalysts can enable efficient and scalable CO_(2)reduction reactions,with an aim of assisting researchers in their design of novel catalysts that may reach industrial applications.
基金National Natural Science Foundation of China(22309032,22109120,and 62104170)Guangdong Basic and Applied Basic Research Foundation(2022A1515011737)+2 种基金Science and Technology Program of Guangzhou(2023A04J1395)GDAS’Project of Science and Technology Development(2021GDASYL-20210102010)Zhejiang Provincial Natural Science Foundation of China(LY23F040001)。
文摘Photocatalytic oxygen reduction for hydrogen peroxide(H_(2)O_(2))synthesis presents a green and costeffective production method.However,achieving highly selective H_(2)O_(2)synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative by-products.Herein,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H_(2)O_(2)and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride(CNRb).The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h^(-1)for H_(2)O_(2)generation and photooxidation rate of 3.75 mM h^(-1)for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion(SCC)efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical formation.This is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product formation.This study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H_(2)O_(2)coupled with biomass valorization.
文摘Objective:To examine the effect of shikonin against streptozotocin(STZ)-induced diabetic retinopathy in rats and elucidate the underlying mechanisms.Methods:Intraperitoneal administration of STZ(65 mg/kg)was used for the induction of diabetic retinopathy in rats.Rats received oral administration of shikonin(10,20,and 30 mg/kg).The blood glucose level,insulin,body weight,and organ weight were estimated.Advanced glycation end products(AGEs)levels in serum and lens as well as protein carbonyl content of the lens were determined.The parameters related to oxidative stress and inflammation,and the levels of nuclear factor erythroid 2-related factor 2(Nrf2),heme oxygenase-1(HO-1),intercellular adhesion molecule-1(ICAM-1),and vascular cell adhesion molecule 1(VCAM-1)were also measured.In addition,quantitative RT-PCR was performed to determine the mRNA expressions.Results:Shikonin treatment decreased glucose level and boosted insulin level,along with an increase in body weight and improved organ weight.It also lowered O2•−,ONOO−,serum and lens AGEs,and protein carbonyl content.Furthermore,shikonin treatment significantly alleviated oxidative stress and inflammation,as evidenced by reduced malonaldehyde,nitric oxide,tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),IL-6,cyclooxygenase-2,prostaglandin E2,protein carbonyl content,and nuclear factor kappa-B,and increased superoxide dismutase,glutathione,catalase,and glutathione peroxidase.Markedly decreased levels of ICAM-1 and VCAM-1,as well as heightened levels of Nrf2 and HO-1,were noticed after treatment with shikonin.Furthermore,the mRNA expressions of TNF-α,IL-1β,IL-6,ICAM-1,VCAM-1,RAGE,collagenⅣ,and fibronectin were significantly downregulated.Conclusions:Shikonin exhibits protective effects against STZ-induced diabetic retinopathy in rats via modulating the Nrf2/HO-1 and NF-κB signaling pathways.
基金supported by the National Natural Science Foundation of China(52301259 and 22208019)the Research Fund Program for Young Scholars of Beijing Institute of Technology。
文摘Electrochemical carbon dioxide reduction reaction(CO_(2)RR)converts CO_(2) into valuable chemicals by consuming renewable electricity at mild conditions,making it a promising approach to achieving carbon neutrality.However,the reaction of CO_(2) with hydroxide ions to form carbonates leads to low carbon utilization and energy efficiency in near-neutral or alkaline CO_(2)RR.The high concentration of protons in acidic media can effectively mitigate carbonate formation and deposition,thereby significantly minimizing carbon loss and energy consumption.Unfortunately,hydrogen evolution reaction(HER)is more kinetically favorable than CO_(2)RR in acidic media.Herein,we comprehensively overview recent progress in acidic CO_(2)RR and propose two strategies derived from the competing reaction pathways of HER and CO_(2)RR:one focuses on regulating the H+mass transport,while the other aims to modulate the intrinsic kinetic activity of CO_(2)RR.The two strategies are designed to compete for the limited active sites on the catalyst surface,inhibit side reactions,and enhance the activity and selectivity of CO_(2)RR.The representative approaches include modulating the interface electric field,constructing a local alkaline environment,and regulating competing adsorption sites.Finally,we also review the technical challenges and future perspectives of acidic CO_(2)RR coupled with membrane electrode assemblies(MEAs).
基金supported by grants from the Beijing Municipal Public Welfare Development and Reform Pilot Project for Medical Research Institutes(PWD&RPP-MRI,JYY2023-6)the R&D Program of Beijing Municipal Education Commission(KZ20231002543).
文摘Background:Dry eye disease(DED)predominantly results from elevated tear film os-molarity,which can not only cause ocular inconvenience but may lead to visual impair-ments,severely compromising patient well-being and exerting substantial economic burdens as well.Astaxanthin(AST),a member of the xanthophylls and recognized for its robust abilities to combat inflammation and oxidation,is a common dietary sup-plement.Nonetheless,the precise molecular pathways through which AST influences DED are still poorly understood.Methods:Therapeutic targets for AST were identified using data from the GeneCards,PharmMapper,and Swiss Target Prediction databases,and STITCH datasets.Similarly,targets for dry eye disease(DED)were delineated leveraging resources such as the Therapeutic Target Database(TTD),DisGeNET,GeneCards,and OMIM databases,and DrugBank datasets.Interactions among shared targets were charted and dis-played using CytoScape 3.9.0.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were conducted to elucidate the functions of pivotal tar-gets within the protein-protein interaction network.Molecular interactions between AST and key targets were confirmed through molecular docking using AutoDock and PyMOL.Molecular dynamics simulations were performed using GROMACS 2022.3.Viability of human corneal epithelial cells(hCEC)was assessed across varying concen-trations of AST.A mouse model of experimental DED was developed using 0.1%ben-zalkonium chloride(BAC),and the animals were administered 100 mg/kg/day of AST orally for 7 days.The efficacy of the treatments was assessed through a series of di-agnostic tests to evaluate the condition of the ocular surface after the interventions.The levels of inflammation and oxidative stress were quantitatively assessed using methods such as reverse transcription-polymerase chain reaction(RT-PCR),Western blot,and immunofluorescence staining.Results:Network pharmacology suggests that AST may alleviate DED by influenc-ing oxidation-reduction signaling pathways and reducing oxidative stress provoked by BAC.In vivo experiments demonstrated an improved overall condition in AST-administered mice in contrast to the control group.Immunofluorescence staining analyses indicated a decrease in Keap1 protein in the corneal tissues of AST-treated mice and a significant increase in Nrf2 and HO-1 protein.In vitro studies demon-strated that AST significantly enhanced cell viability and suppressed reactive oxy-gen species expression under hyperosmotic(HS)conditions,thereby protecting the human corneal epithelium.Conclusion:AST is capable of shielding mice from BAC-induced DED,decelerating the progression of DED,and mitigating oxidative stress damage under HS conditions in hCEC cells.The protective impact of AST on DED may operate through stimulating the Keap1-Nrf2/HO-1 signaling pathway.Our research findings indicate that AST may be a promising treatment for DED,offering new insights into DED treatment.
基金supported by the Hebei province Natural Science Foundation(No.B2023108012)the Science Research Project of Hebei Education Department(No.BJK2024137)+2 种基金the S&T Program of Xingtai(No.2023ZZ096)the National Natural Science Foundation of China(No.62004143)the Key R&D Program of Hubei Province(No.2022BAA084)。
文摘A meticulous design of the local environment at the interface between active species and the support,aimed at optimizing the adsorption of H_(2)O molecules and BH_(4)^(-)anion,offers an ideal strategy for enhancing hydrogen generation via Na BH4hydrolysis through dual activation pathways.Theoretical predictions based on d-band center analysis and electron transfer calculations suggest that introducing-OH functional groups induce charge redistribution,enhancing charge concentration on alk-Ti_(3)C_(2)and facilitating the adsorption and activation of dual active species,H2O molecules and BH4-anion.Inspired by these predictions,the optimized alk-Ti_(3)C_(2)/Ru Oxcatalyst demonstrates the highest catalytic activity,achieving a hydrogen generation rate(HGR)of 9468 m L min^(-1)gcat.^(-1).Both experimental data and theoretical analyses confirm that the-OH functional groups promote charge enrichment on alk-Ti_(3)C_(2),optimizing the adsorption of H_(2)O molecules and BH_(4)^(-)anion,and reducing the dissociation energy barrier of the*OH–H-TS intermediate.This dual activation pathways mechanism lowers the activation energy for Na BH4hydrolysis,significantly enhancing the HGR performance.These findings,guided by theoretical insights,establish alk-Ti_(3)C_(2)/Ru Oxas an efficient catalyst for Na BH4hydrolysis and provide a strong foundation for future hydrogen generation catalyst designs.
基金This work was supported by a grant from NSFC (No.39570188)
文摘WT5”BZ] To study the molecular mechanism of the stimulatory effect of low dose radiation(LDR) on T cell activation. [WT5”BX]Methods.[WT5”BZ] Thymocytes from Kunming mice exposed to whole body irradiation(WBI) with different doses of X rays were analyzed for the changes in signal molecules of the phospholipase C phosphatidylinositol biphosphate(PLC IP2) and G protein adenylate cyclase(AC) pathways. [WT5”BX]Results.[WT5”BZ]It was found that[Ca 2+ ] i increased in response to doses within 0 2 Gy which was most marked after 0 075 Gy and the increase was accentuated in the presence of Con A. The changes in CD3 and calcineurin(CN) expression of the thymocytes followed the same pattern as the alterations in [Ca 2+ ] i after LDR. The expression of α,β1 and β2 isoforms of protein kinase C(PKC) was all up regulated after 0 075 Gy with the increase in PKC β1 expression being most marked. The cAMP/cGMP ratio and PKA activity of the thymocytes was lowered after low dose radiation and increased after doses above 0 5 Gy in a dose dependent manner, thus giving rise to J shaped dose response curves. The Ca antagonist TMB 8 and cAMP stimulant cholera toxin suppressed the augmented thymocyte proliferation induced by LDR. [WT5”BX]Conclusion.[WT5”BZ]Data presented in the present paper suggest that activation of the PLC PIP2 signal pathway and suppression of the AC cAMP signal pathway are involved in the stimulation of the thymocytes following WBI with low dose X rays.
